Update the documentation

Author: habarthierry-hue

website/docs/idserver/migrations/duende.md

@@ -0,0 +1,63 @@
+# Migrating from Duende to SimpleIdServer
+
+If you're currently using Duende IdentityServer version 7, migrating to SimpleIdServer is a smooth and straightforward process.
+With the help of our migration tool, you can quickly transition your identity server without hassle.
+
+## How to Migrate
+
+To begin the migration, you will need to install the `SimpleIdServer.IdServer.Migrations.Duende` NuGet package on your identity server.
+This package provides the necessary tools to facilitate the migration from Duende to SimpleIdServer.
+
+```cmd title="cmd.exe"
+dotnet add package SimpleIdServer.IdServer.Migrations.Duende
+```
+
+Once the NuGet package is installed, follow these steps to configure your migration:
+
+Edit the Program.cs file; Add two essential functions:
+
+* **EnableMigration**: This function registers the dependencies needed to execute the migration.
+
+* **AddDuendeMigration** : This function registers the dependencies for migrating data from a Duende database to a SimpleIdServer database. It takes a lambda expression as a parameter, where you can specify the database connection string.
+
+Here's an example of how to configure the migration:
+
+```csharp title="Program.cs"
+builder.AddSidIdentityServer()
+    .EnableMigration()
+    .AddDuendeMigration(a =>
+    {
+        a.UseSqlServer(""); // Add your connection string here
+    });
+```
+
+## Running the Migration
+
+Once the migration is set up, you can execute it in two ways:
+
+1. **Manual Execution via Admin Portal**: You can trigger the migration manually by navigating to the `Migrations` tab in the administration portal of your identity server.
+
+![Authenticate](./imgs/migrations.png)
+
+2. **Automatic Execution on Server Startup**: If you want the migration to run automatically when the identity server starts, you can call the `LaunchMigration` function. This function takes a parameter, the realm, which determines where the data will be migrated. By default, this value is set to `master`.
+
+Example :
+
+```csharp title="Program.cs"
+app.Services.LaunchMigration();
+```
+
+## Entities Migrated
+
+The following entities will be migrated from Duende IdentityServer to SimpleIdServer:
+
+| Duende Entity     | SimpleIdServer Entity |
+| ----------------- | --------------------- |
+| ApiScopes         | Scope                 |
+| IdentityResources | Scope                 |
+| ApiResource       | ApiResource           |
+| Client            | Client                |
+| Groups            | Groups                |
+| Users             | Users                 |
+
+With this migration process, your identity server's data is transferred seamlessly to SimpleIdServer, ensuring minimal disruption and a smooth transition.

website/docs/idserver/migrations/imgs/migrations.png

@@ -100,6 +100,13 @@ const sidebars = {
             'idserver/hosting/nginx',
             'idserver/hosting/loadbalancing'
           ]
+        },
+        {
+          type: 'category',
+          label: 'Migrations',
+          items: [
+            'idserver/migrations/duende'
+          ]
         }
       ]
     },